STABLE POLYALUMINIUM-FREE CHLOROSULPHATES Russian patent published in 2019 - IPC C01F7/00 C02F1/52 B01D21/01 C01B17/45 

FIELD: technological processes.

SUBSTANCE: group of inventions can be used in treating waste water as flocculants and coagulants. High-sulphated, high-basic polyaluminium chlorosulphate (PACS) compositions have basicity of 55 to 75 % and the formula: Al(OH)_xCl_(3-x-2y)(SO₄)_y, where 1.78≤x≤2.02, 0.03≤y≤0.45 and 1.8≤x+y/2≤2.1; ratio of Al:SO₄ ranges from 2 to 34; Al:Cl ratio ranges from 0.9 to 3.0; ratio of Al:OH ranges from 0.5 to 0.6 and the average molecular weight of PACS is greater than or equal to 95 and less than or equal to 111. Additionally, the salts present in the PACS composition contain from 0 to 1.0 % sodium chloride by weight and from 0 to 1.0 % sodium sulphate by weight. Compositions are obtained by mixing solid aluminum hydroxychloride containing 1.5 or less moles of hydrated water with an aqueous solution of aluminum sulphate, holding the obtained suspension for a period of time sufficient to convert the suspension into a transparent or slightly cloudy solution. Package in the form of a container containing a mixture of two components – aluminum hydroxychloride and aluminum sulphate, is used in treatment of waste water. Said mixture contains from 0.75 to 20 parts of aluminum hydroxychloride per 1 part of aluminum sulphate in terms of dry mass, and said aluminum hydroxychloride contains less than 3 moles of hydration water.

EFFECT: invention provides high efficiency and stability of the obtained compositions as heat-resistant coagulants when working with cold or very turbid waters in a wide pH range.

19 cl, 2 ex